Page 175 of 558

MPI – Troubleshooting13-63
ENGINE-ECU INSPECTION
TERMINAL VOLTAGES
Engine ECU connector
Terminal
No.Check itemCheck condition (Engine condition)Normal condition
1No.1 injectorWhile engine is idling after having been warmed up,
suddenly depress the accelerator pedal
Momentarily drops
slightlyfrom 1114V
14No.2 injector
suddenly depress the accelerator pedal.slightly from 11 – 14 V.
2No.3 injector
15No.4 injector
3Fuel pressure control
valve
Ignition switch: ONSystem voltage
valve
Engine: Cranking to idling (within about two minutes)0 – 3 V to sytem
voltage
4Stepper motor coil (A1)Engine: Immediately after engine has been started
f
or warming up
Changes repeatedly
f
rom system voltage
17Stepper motor coil (A2)
for warming upfrom system voltage
to 0 – 6 V and from 0
6 V to system5Stepper motor coil (B1)– 6 V to system
voltage.
18Stepper motor coil (B2)
6Secondary air control
solenoid valveIgnition switch: ONSystem voltage
8Fuel pump relayIgnition switch: ONSystem voltage
Engine: Idling0 – 3 V
10Power transistor unit
(A)Engine speed: 3,000 r/min0.3 – 3.0 V
23Power transistor unit
(B)
11Wastegate solenoid
valve
Ignition switch: ONSystem voltage
valve
Engine: At idle after having been warmed up (when
premium gasoline is used)0 – 3 V
12Power supplyIgnition switch: ONSystem voltage
25
19Air flow sensor reset
signal
Engine: Idling0 – 1 V
signal
Engine speed: 3,000 r/min6 – 9 V
20Fan motor relay (HI)
Fan not operating (coolant temperature: 90C or
below)System voltage
Fan at high speed (coolant temperature: 105C or
above)0 – 3 V
Page 176 of 558

MPI – Troubleshooting13-64
Terminal
No.Normal condition Check condition (Engine condition) Check item
20Radiator fan motor
relay (HI)
Radiator fan not operating (coolant temperature:
95C or below)System voltage
Radiator fan at high speed (coolant temperature:
105C or above)0 – 3 V
21Fan motor relay (LOW)
Fan not operating (coolant temperature: 95C or
below)System voltage
Fan at low speed (coolant temperature: 95 – 100C)0 – 3 V
21Radiator fan motor
relay (LOW)
Radiator fan not operating (coolant temperature:
95C or below)System voltage
Radiator fan at low speed (coolant temperature: 95
– 105C)0 – 3 V
22A/C relayEngine: Idling
A/C switch: OFF to ON (Compressor is being
driven.)System voltage, or 6
V or more instanta-
neously to 0 – 3 V
32A/C condenser fan
motor relay (HI)
A/C condenser fan not operating (A/C switch: ON,
coolant temperature: 105C or below)System voltage
A/C condenser fan at high speed (A/C switch: ON,
coolant temperature: 105C or above)0 – 3 V
33Alternator G terminalEngine: Warm, idle (radiator fan: OFF)
Headlamp: OFF to ON
Brake lamp: OFF to ON
Rear defogger switch: OFF to ONVoltage rises by 0.2 –
3.5 V.
34A/C condenser fan
motor relay (LOW)
A/C condenser fan not operating (A/C switch: OFF,
coolant temperature: 105C or below)System voltage
A/C condenser fan at low speed (A/C switch: OFF,
coolant temperature: 105C or above)0 – 3 V
36Engine warning lampIgnition switch: OFF → ON0 – 3 V → System
voltage (After several
seconds have
elapsed)
37Power steering fluid
pressure switchEngine: Idling after
warming upWhen steering wheel is
stationarySystem voltage
When steering wheel is
turned0 – 3 V
38Control relayIgnition switch: OFFSystem voltage
Ignition switch: ON0 – 3 V
39Fuel pump relay No.2While engine is idling, suddenly depress the
accelerator pedal.Momentarily rises
slightly from 0 to 3 V.
40Exhaust temperature
warning lampIgnition switch: OFF to ON0 – 3 V to system
voltage (After several
seconds have
elapsed)
Page 177 of 558

MPI – Troubleshooting13-65
Terminal
No.Normal condition Check condition (Engine condition) Check item
41Alternator FR terminalEngine: Warm, idle (radiator fan: OFF)
Headlamp: OFF to ON
Brake lamp: OFF to ON
Rear defogger switch: OFF to ONVoltage drops by 0.2 –
3.5 V.
45A/C switchEngine: Idle speedTurn the A/C switch OFF0 – 3 V
Turn the A/C switch ON
(A/C compressor is oper-
ating)System voltage
60Oxygen sensor heater
Engine: Idling0 – 3 V
Engine speed: 5,000 r/minSystem voltage
71Ignition switch-STEngine: Cranking8 V or more
72Intake air temperature
sensorIgnition switch: ONWhen intake air tempera-
ture is 0C3.2 – 3.8 V
When intake air tempera-
ture is 20C2.3 – 2.9 V
When intake air tempera-
ture is 40C1.5 – 2.1 V
When intake air tempera-
ture is 80C0.4 – 1.0 V
76Oxygen sensorEngine: Running at 2,000 r/min after having been
warmed up (Check using a digital type voltmeter)0 ↔ 0.8 V
(Changes repeatedly)
80Backup power supplyIgnition switch: OFFSystem voltage
81Sensor impressed
voltageIgnition switch: ON4.5 – 5.5 V
82Ignition switch-IGIgnition switch: ONSystem voltage
83Engine coolant
temperature sensorIgnition switch: ONWhen engine coolant
temperature is 0C3.2 – 3.8 V
When engine coolant
temperature is 20C2.3 – 2.9 V
When engine coolant
temperature is 40C1.3 – 1.9 V
When engine coolant
temperature is 80C0.3 – 0.9 V
84Throttle position sensorIgnition switch: ONSet throttle valve to idle
position0.3 – 1.0 V
Fully open throttle valve4.5 – 5.5 V
85Barometric pressure
sensor
Ignition switch: ONWhen altitude is 0 m3.7 – 4.3 V
sensor
When altitude is 1,200 m3.2 – 3.8 V
86Vehicle speed sensorIgnition switch: ON
Move the vehicle slowly forward0 ↔ 5 V
(Changes repeatedly)
Page 178 of 558
MPI – Troubleshooting13-66
Terminal
No.Normal condition Check condition (Engine condition) Check item
87Idle position switchIgnition switch: ONSet throttle valve to idle
position0 – 1 V
Slightly open throttle
valve4 V or more
88Camshaft position
sensor
Engine: Cranking0.4 – 3.0 V
sensor
Engine: Idle speed0.5 – 2.0 V
89Crank angle sensorEngine: Cranking0.4 – 4.0 V
Engine: Idle speed1.5 – 2.5 V
90Air flow sensorEngine: Idle speed2.2 – 3.2 V
Engine speed: 2,000 r/min
Page 179 of 558

MPI – Troubleshooting13-67
RESISTANCE AND CONTINUITY BETWEEN HARNESS SIDE CONNECTORS AND TERMINALS
Engine-ECU Harness Side Connector Terminal Arrangement
Terminal No.Inspection itemNormal condition (Check condition)
1 – 12No.1 injector2 – 3 Ω (At 20C)
14 – 12No.2 injector
2 – 12No.3 injector
15 – 12No.4 injector
3 – 12Fuel pressure control valve28 – 36 Ω (At 20C)
4 – 12Stepper motor coil (A1)28 – 33 Ω (At 20C)
17 – 12Stepper motor coil (A2)
5 – 12Stepper motor coil (B1)
18 – 12Stepper motor coil (B2)
6 – 12Secondary air control solenoid valve28 – 36 Ω (At 20C)
11 – 12Wastegate solenoid valve62 – 74 Ω (At 20C)
60 – 12Oxygen sensor heater
11 – 18 Ω (at 20C)
13 – Body earthEngine-ECU earthContinuity established (0 Ω)
26 – Body earth
72 – 92Intake air temperature sensor5.3 – 6.7 kΩ (When intake air temperature is 0C)
2.3 – 3.0 kΩ (When intake air temperature is 20C)
1.0 – 1.5 kΩ (When intake air temperature is 40C)
0.30 – 0.42 kΩ (When intake air temperature is 80C)
74 – 77High temperature sensor3 Ω or less
83 – 92Engine coolant temperature sensor5.1 – 6.5 kΩ (When coolant temperature is 0C)
2.1 – 2.7 kΩ (When coolant temperature is 20C)
0.9 – 1.3 kΩ (When coolant temperature is 40C)
0.26 – 0.36 kΩ (When coolant temperature is 80C)
87 – 92Idle position switchContinuity established (when throttle valve is at idle
position)
No continuity (when throttle valve is slightly open)
91 – Body earth–Continuity established
Page 180 of 558
MPI – On-vehicle Service13-68
ON-VEHICLE SERVICE
FUEL PUMP RESISTOR CHECK
Standard value: 0.45 – 0.65 Ω
The inspection procedures are the same as for the preceding
year-models.
FUEL PUMP RELAY No.2 CONTINUITY CHECK
Battery voltageTerminal No.
1234
Not supplied
Supplied
ENGINE CONTROL RELAY AND FUEL PUMP
RELAY CONTINUITY CHECK
Battery voltageTerminal No.
1234
Not supplied
Supplied
Equipment side connector for engine
control relay and fuel pump relay
Fuel pump relay
Engine control relay
Page 200 of 558

REAR AXLE – Special Tools / Troubleshooting 27-4
MB990925
Brass bar
Bar (one-touch type)Toolbox
Installer adapter
Tool number (MB990925)O.D. mmTool number (MB990925)O.D. mm
AMB99092639.0AMB99093363.5
MB99092745.0MB99093467.5
MB99092849.5MB99093571.5
MB99092951.0MB99093675.5
MB99093054.0MB99093779.0
MB99093157.0BMB990938–
MB99093261.0CMB990939–
TROUBLESHOOTING
BASIC TROUBLESHOOTING CONDITIONS
Refer to Group 00 – How to Use Troubleshooting / Inspection Service Points.
NOTE
Before starting the troubleshooting procedure, make sure that the following items have been checked
okay.
The correct steering wheel has been properly installed in the neutral position of the steering column
shaft.
Tire and wheel sizes are correct with correct specifications. Inflation pressure, balance, and wear
conditions are okay.
Wheel alignment is correct.
The engine, suspension, and other parts have not been remodeled so as to affect the AYC system.
DIAGNOSIS FUNCTION
READING THE DIAGNOSIS CODE
Read the diagnosis code using an MUT-II tester or the AYC warning lamp.
(Refer to Group 00 – How to Use Troubleshooting / Inspection Service Points.)
ERASING THE DIAGNOSIS CODE
Refer to Group 00 – How to Use Troubleshooting / Inspection Service Points.
Page 216 of 558

REAR AXLE – Troubleshooting 27-20
5. INSPECTION CHART FOR TROUBLE SYMPTOMS
Trouble symptomInspection
procedure No.Ref. page
Communication between MUT-II and the whole system is not possible.127-20
Communicatio between MUT-II and AYC-ECU is not possible.227-21
AYC warning lamp does not light up when the ignition key is turned to “ON” (engine
stationary).327-22
AYC warning lamp remains lit up after the engine has started.427-23
AYC is inoperative.
Unable to start or accelerate on slippery road surfaces.527-23
Rear tires are noisy during low-speed cornering.
Vehicle skews.627-24
6. INSPECTION PROCEDURE FOR TROUBLE SYMPTOMS
INSPECTION PROCEDURE 1
Communication between MUT-II and the whole system is
not possible.
Probable cause
The cause may be a malfunction of the power supply circuit or the ground circuit
of the diagnosis connector.Defective diagnosis connector
Defective harness or connector
NG
Check and repair the harness between
power supply and diagnosis connector.
OK
Check the trouble symptom.
NG
Check and repair the harness between
body ground and diagnosis connector.
OK
Check the trouble symptom.
OK
Replace MUT-II.
Check the following connectors:
B-22, B-50NG
Repair
OK
Measure at B-22 diagnosis connector.
Disconnect the connector and
measure at the harness side.
Continuity across 4/5 and body
ground
OK:ConductingNG
Measure at B-22 diagnosis combina-
tion meter connector.
Voltage across 16 and body ground
OK:System voltageNGCheck the following connectors:
B-22, B-49, B-75, B-73NG
Repair